Abstract: A method of measuring state of vigilance of a pilot by a measuring device to measure time between which a sound wave is emitted by a loudspeaker in the piloting station of an aircraft and is received by the microphone of a headset of a pilot and to calculate coordinates of a sphere centered on the loudspeaker and on the perimeter of which the microphone is situated. Calculation of points of intersection of spheres centered on different loudspeakers provides possible microphone positions in the space of the piloting station. These positions are those of the head of the pilot when the headset is used. Via the knowledge of at least one possible position of the head of the pilot in the piloting station, the measuring device can measure the state of vigilance of the pilot and to alert in case of a confirmed lack of vigilance of the pilot.

Abstract: A method of measuring state of vigilance of a pilot by a measuring device to measure time between which a sound wave is emitted by a loudspeaker in the piloting station of an aircraft and is received by the microphone of a headset of a pilot and to calculate coordinates of a sphere centered on the loudspeaker and on the perimeter of which the microphone is situated. Calculation of points of intersection of spheres centered on different loudspeakers provides possible microphone positions in the space of the piloting station. These positions are those of the head of the pilot when the headset is used. Via the knowledge of at least one possible position of the head of the pilot in the piloting station, the measuring device can measure the state of vigilance of the pilot and to alert in case of a confirmed lack of vigilance of the pilot.